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Meanest mufflers for a 408 stoker?

  • Thread starter Thread starter pdw5000
  • Start date Start date Aug 6, 2008
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pdw5000

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#1
  • Aug 6, 2008
  • #1
I'm installing a 408 stoker in my 68 stang. It has a cam with over .600 lift so it should thump pretty good. My current exhaust system is a custom bent 2-1/2" pipe with x-pipe and dual 40 series flowmasters dumped out back.

I want an exhaust system that will sound mean as hell and be as loud as possible. I don't want any glass packs or open headers. Short of that what is the best mufflers/setup out there?

I was going to try my current setup and see how it sounds but if I don't like it I was thinking about switching out to spintech or dynomax race mufflers and dumping them before the rear end.
 

JC6715

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Hillsboro, Oregon
Aug 6, 2008
#2
  • Aug 6, 2008
  • #2
I'm putting in a 331 and currently have Hooker Aerochambers with h-pipe dumped before the axle. Haven't put in the new engine yet, but if the current setup doesn't sound right, I'm going to switch over to Moroso's Spiral Flow race mufflers and make some NASCAR style boomtubes for side exit. There are some clips on youtube of the spiral flows, but not on a Mustang...

Not sure how much that helps, but from what I've heard the spiral flows are loud and tough sounding.
 

iskwezm

10 Year Member
May 24, 2005
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Aug 6, 2008
#3
  • Aug 6, 2008
  • #3
I have a single 4" Borla thats pretty loud...............a little too loud
 

blown65

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Jul 7, 1999
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Aug 6, 2008
#4
  • Aug 6, 2008
  • #4
Prob 3" Spintechs ProStreets would sound good. 3" Dynomax Race Bullets would also. Both are pretty loud and you will hear the nice cam in the engine. If you want more mellow at idle and loud at WOT then go with some Magnaflow mufflers. I just hate them cause you can have a very aggressive engine, and it totally mellows it out. Mine are sitting on the floor collecting dust. hehe
 
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pdw5000

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Yea...I'm not a big fan of magnaflow because they don't sound good until you get on it.
 
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Stang427W

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SLP Loudmouths sound pretty cool, and are quite loud.... They are not really mufflers, they are pretty much resonators.

http://www.americanmuscle.com/slp-loudmouth2-bullet-mufflers.html


Take a look there...
 
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D.Hearne

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#7
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If you really want loud, just remove the mufflers altogether, replace them with straight pipe. I've got 2-1/2" Turbo tubes behind my 331, these are 18" long, basically perforated 2-1/2 pipe, surronded by crimped in three sections 4" pipe. Bought em on ebay from a guy who custom builds em with the original machine. Got a budy who lives a half mile away that can hear the car everytime I fire it up. Tailpipes are angle cut 12" sections straight off the mufflers. Nice sound, with a raspy tune when you let off the gas.
 

69gmachine

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Dec 2, 2004
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Southern Maryland
Aug 7, 2008
#8
  • Aug 7, 2008
  • #8
Any of the straight thru muffler designs will give you almost open header sound. I'm still using the Magnaflow mufflers that came with the kit. Not much point in turning the radio on. I'm ready to put some Turbo mufflers on instead.
 

Hack

15 Year Member
Mar 23, 2004
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Minneapolis
Aug 7, 2008
#9
  • Aug 7, 2008
  • #9
Meanest muffler? How about a turbocharger!
 

brianj5600

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Sep 19, 2003
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Middle TN
Aug 7, 2008
#10
  • Aug 7, 2008
  • #10
Hack said:
Meanest muffler? How about a turbocharger!
Click to expand...

My car with an open down pipe is about as quiet as bullet mufflers.
 

SadbutTrue

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May 1, 2002
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Aug 7, 2008
#11
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Well, sicne no one else does... 1 vote for dual chamber flows. If you're going for sound, they can't be beat, especially since he has stated he wants them to be loud without geting on it. I will say tha tmy 351 combo (in sig) and its flowmasters border on ridiculous... but in such a good way Sure, you lose a couple horses from the straight-through designs but with a 408 you'll have a few to spare.
 

blown65

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#12
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SadbutTrue said:
Well, sicne no one else does... 1 vote for dual chamber flows. If you're going for sound, they can't be beat, especially since he has stated he wants them to be loud without geting on it. I will say tha tmy 351 combo (in sig) and its flowmasters border on ridiculous... but in such a good way Sure, you lose a couple horses from the straight-through designs but with a 408 you'll have a few to spare.
Click to expand...


The SpinTechs have a very similar sound to them compared to the flowmasters. That and they don't seem to have the big hp loss seen on certain motors that the flows seem to.
 
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silverbluebp

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Aug 13, 2003
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Aug 7, 2008
#13
  • Aug 7, 2008
  • #13
Here's a link to my 66, 289, 2 1/2" pipe, X-pipe, Dynomax race bullets and side exit. It's pretty loud!

YouTube - 1966 Mustang sound bite 1
 
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pdw5000

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#14
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If I was to switch to a different muffler would it be worth switching from 2 1/2" to 3" exhaust? I expect to see 500 hp/tq from this motor and I want it to breath as good as possible. How much power do you think it would be worth switching to larger exhaust? Would it justify the cost?
 

SadbutTrue

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#15
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blown65 said:
The SpinTechs have a very similar sound to them compared to the flowmasters. That and they don't seem to have the big hp loss seen on certain motors that the flows seem to.
Click to expand...

Now that re-read the OPs original post, it sounds like he already has dual chamber flows. If he wants to keep an actual muffler, its gonna be hard to sound much more aggressive than that with that pipe diameter. Different tones, definitely... but overall meaner? Doubt it.

500 hp is probably where you want to start switching to 3" pipes. Whether it'd be worth buying a whole new exhaust system... I have no idea.

On a semi-related note, if someone has an article/chart with dynos/etc that shows how good or bad flowmasters really are compared to straight through and OEM style mufflers, I'd lvoe to see it. I mean, a chambered muffler can't flow as much as well as a straight through (you just look at the designs and thats obvious), but it'd be interesting to see what the actual difference is.
 

blown65

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#16
  • Aug 7, 2008
  • #16
SadbutTrue said:
Now that re-read the OPs original post, it sounds like he already has dual chamber flows. If he wants to keep an actual muffler, its gonna be hard to sound much more aggressive than that with that pipe diameter. Different tones, definitely... but overall meaner? Doubt it.

500 hp is probably where you want to start switching to 3" pipes. Whether it'd be worth buying a whole new exhaust system... I have no idea.

On a semi-related note, if someone has an article/chart with dynos/etc that shows how good or bad flowmasters really are compared to straight through and OEM style mufflers, I'd lvoe to see it. I mean, a chambered muffler can't flow as much as well as a straight through (you just look at the designs and thats obvious), but it'd be interesting to see what the actual difference is.
Click to expand...

Im over 500hp and with 2 1/2" with the spintechs it sounds very mean. However I had to get rid of the tailpipe section cause it was causing some odd noises that I didnt like. Even when I had my Magnaflow mufflers on, it did the same thing. That being said, it was a cheapie setup from a muffler shop in town with crush bend ends, which is terrible for flow. Im sure a 2 1/2" mandrel bent setup would of been 100% better.

I am though switching to a 3" exh system with Dynomax Race bullets, and going to sell my 2 1/2 Spintech mufflers. Not because I dont like them, just I dont want to be taking exh on and off anymore.
 

SadbutTrue

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#17
  • Aug 8, 2008
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blown65 said:
Im over 500hp and with 2 1/2" with the spintechs it sounds very mean. However I had to get rid of the tailpipe section cause it was causing some odd noises that I didnt like. Even when I had my Magnaflow mufflers on, it did the same thing. That being said, it was a cheapie setup from a muffler shop in town with crush bend ends, which is terrible for flow. Im sure a 2 1/2" mandrel bent setup would of been 100% better.

I am though switching to a 3" exh system with Dynomax Race bullets, and going to sell my 2 1/2 Spintech mufflers. Not because I dont like them, just I dont want to be taking exh on and off anymore.
Click to expand...

Ha, I have no doubt. Even my stock head/cam 351w sounded pretty mean with American Thunder system and long tubes. Sounds ridiculous now (2.5" pipes both times).

However, most manufacturers recommend 2.5" piping for applications up to 450 hp. Obviously, depending on your configuration that point may fluctuate some, but once you go to 400+cid, 500+ hp and some rpms, that extra flow becomes helpful. On the flipside, if it were me I'd have a hard time ditching a fairly new exhaust system to spend $500+ on a new system unless I knew it was gonna bring some serious gains. The OP will probably gain some power from 3" pipes, but I don't have the experience to know whether it'd be 5 hp or 30 hp.

Because I'm cheap, I might not even bother if it was 30 hp, since my exhaust system is 4 years old and in perfect shape, But to the OP, it might eb worth it. But if my exhaust system were old and shot anyway, I'd go ahead and use that as an excuse to upgrade.

And I'm sure it will sound plenty mean, even with 2.5" pipes.

Also to the OP... keep in mind having true longtube headers helps a lot with the 'mean' sound. If you weren't planning on those (or have them already) i'd recommend that first.
 
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